Split gas burner

ABSTRACT

A gas-fired cooking grill includes a cooking and smoke-retaining enclosure and a gas burner within the enclosure, the burner being an integral cast hollow structure having two distinct, independently controlled burner portions serving different parts of the cooking rack.

United States Patent Drennan Feb. 1, 1972 [54] SPLIT GAS BURNER [72]lnventor: Wendell M. Brennan, Evansville, Ind.

[73] Assignee: Arkla Industries, Inc., Evansville, Ind.

[22] Filed: Sept. 18, 1969 211 Appl. No.: 859,156

[52] US. Cl. ..126/41 R, 239/444, 431/278 [51] Int. Cl. ..A47j 37/07,F23d 13/00 [58] Field of Search ..l26/4l; 431/278; 239/444 [56]References Cited UNITED STATES PATENTS 973,498 10/1910 Geurink ..431/2781,224,157 5/1917 Fry ..43l/278 X 1,328,589 1/1920 Roberts ..43l/2782,790,434 4/1957 Del Francia 126/41 3,295,509 1/1967 Harvey 126/41 UX3,386,432 6/1968 Hanson.... ..l26/41 3,498,284 3/1970 Swaddey 126/41Primary Examiner-Charles J. Myhre Attorney-Cushman, Darby & Cushman [5 7ABSTRACT A gas-fired cooking grill includes a cooking andsmoke-retaining enclosure and a gas burner within the enclosure, theburner being an integral cast hollow structure having two distinct,independently controlled burner portions serving different parts of thecooking rack.

8 Claims, 3 Drawing Figures PATENTEDFEB 1m 3,638,635

SHEET 2 BF 2 INVENTOR ATTORNEYfl SPLIT GAS BURNER This invention relatesto gas-fired cooking grills and in particular to an improved gas burnerfor such grills.

Gas-fired cooking grills of contemporary construction generally includean open-topped boxlike enclosure in which are disposed a horizontalcooking rack, a layer of looselypacked ceramic briquets supported belowthe cooking rack and a gas burner located below the layer of briquettes.Usually the enclosure is provided with a removable or hinged top so thatsmoke will be retained in the enclosure, the smoke being generatedduring use by the vaporization and combustion of fat and meat juicesdripping on to the heated briquets. Heat reaches the food on the cookingrack in the form of radiant heat from the briquets and in the form ofhot gases rising through the layer of briquets from the gas flame.

In conventional gas-fired grills the gas burner is so shaped andarranged that heat is supplied substantially uniformly over the wholehorizontal cross-sectional area of the enclosure. This arrangement hasin the past been deemed desirable, because each piece of food on thegrill, or all portions of a large piece, will receive about the sameamount of heat, whereby it is unnecessary to shift the position of thepieces or piece during cooking. 7

It has been observed, however, that in grills of substantial size thereis a need to adapt part of the cooking area to operate in a differentmanner from another part, either in terms of temperature or in terms ofa difference in the type of heat energy. For example, if one part of thebed of briquettes is heated by the gas flame and one part is not soheated, then food placed over the unheated briquettes will be cookedprimarily by radiant heat, whereas food placed over the directly heatedbriquettes will be cooked by direct heat including the hot gases fromthe burner flame. Greasy meat, which may tend to cause flareups ifcooked over direct heat, can be cooked by radiant or indirect heat witha much reduced tendency to flare up.

Temperature control of different parts of the cooking area is desirable,for example, when several steaks are being prepared simultaneously andit is desired to cook one to a greater degree than another. This can beaccomplished most simply if one part of the cooking rack, say one-half,is maintained at high temperature and the other part is maintained at alower temperature. Also, when a plurality of different sized pieces ofmeat, such as chicken pieces, pork chops or spare ribs, are beingcooked, it is much easier to avoid overcooking the smaller or thinnerpieces if part of the cooking rack is at a lower temperature than theremainder of the rack.

The present invention provides a simply constructed gas burner which isinternally partitioned, or split into at least two distinct sections sothat each section can be operated independently of the other section.The burner, when properly arranged below the briquettes in a cookinggrill and provided with appropriate independent gas control means,permits the operator to adjust the temperature of the different parts ofthe cooking rack for the various purposes described above.

The invention will be further understood from the following detaileddescription of two exemplary embodiments taken with the drawing inwhich:

FIG. I is a front elevational view, partly broken away, of a gas-firedcooking grill embodying the improved gas burner;

FIG. 2 is a plan view of the gas burner of FIG. 1 looking in thedirection of arrows 22; and

FIG, 3 is a plan view of a modification of the burner of FIG. 2.

Referring to FIG. 1 there is shown a gas-fired cooking grill whichincludes a typical cooking enclosure mounted on a post 12 which in turnis supported on a base 13. The cooking enclosure 10 is a boxlikestructure having a one-piece cast metal bottom section 14 and aone-piece cast metal top section 16 which is hinged to the rear wall ofthe bottom section 14 as at 18. The floor 20 of bottom section 14 may beprovided with apertures 22 which admit secondary combustion air duringoperation. An aperture 23 in one end wall permits entry of a lightedmatch. The bottom section 14 rests directly on the upper end of the postT2, the latter being loosely telescoped into a downwardly projectingsleeve 24 which is secured to the lower surface of the floor 20.

Within the bottom section 14 of the enclosure 10 is a gas burner 25,which embodies the principles of the present invention, together withthe usual cooking rack 26 and layer of ceramic briquettes 28, the latterbeing supported on a grate 30 which may be similar in construction tothe cooking rack 26. The rack 26 and the grate 30 are removablysupported in any suitable manner as by resting on lips 32 and 34 whichextend inwardly from the front and rear walls of the bottom section 14.As shown, the cooking rack 26 is in two parts which may be supported oneither the lip 32 or a higher lip 32a.

All of the above, with the exception of the construction of the burner25, are more or less conventional in gas grills being manufactured atthe present time. The burner 25, according to the present invention, isa unitary hollow metal structure defining at least two arms which extendhorizontally under different parts of the cooking rack 26, each of thearms receiving gas from a separate, adjustable gas delivery means sothat the operator of the grill can adjust the temperature of thedifferent parts of the cooking rack.

In the embodiment of FIGS. 1 and 2 the burner 25 is H- shaped in overallplan view and is constructed internally to define two arms 36 and 38each of which is generally U- shaped. The arm 36 is disposed below theleft part of the cocking rack 26, and the arm 38 is disposed below theright part of the cooking rack 26. While an H-shape is usually preferredfrom the standpoint of ease of construction and operation, other shapessuch as X-shapes or Z-shapes may be employed.

Preferably the burner 25 is constructed as a one-piece in- 'tegrallycast structure by a suitable one-step casting technique which providesfor both the hollow interior and a continuous row of gas apertures 46around the whole periphery of the structure. Conveniently the mold willhave two parts, one of which defines the contour of the upper half ofthe burner 25 and the other of which defines the contour of the lowerhalf. The row of apertures 46 follows the mold separation line 48 seenin FIG. I. Also as seen in FIG. 1, the upper portion of the burner 25includes a laterally projecting lip 50 which extends along the entireperiphery of the structure. A vertically disposed integral internalpartition 52 extends the length of the bar of the H to separate the arms36 and 38.

In the bottom wall of the burner are cast two spaced-apart gas inletopenings 54 and 58 which are disposed on opposite sides of the partition52. Projecting downwardly from the bottom burner wall at each corner isan integral foot 60 which rests on the upper surface of the bottom wall20 of the enclosure 10 thereby supporting the burner 25. Positioningflanges 62 on the wall 20 are provided for preventing the burner 25 fromslipping laterally after it has been lowered into position.

A separate gas delivery means is associated with each of the arms 36 and38. As shown, each delivery means includes a vertically disposed venturidelivery tube 64 having a flanged upper end connected as by screws 63 toa boss 65 on the bottom of the burner 25 so as to be in communicationwith one of the openings 54 or 58. The lower end of the tube 64 is incommunication with a venturi mixer 66. The latter, which may be ofconventional construction, is a device for receiving gas from a supplyand mixing it with primary combustion air which is drawn into the deviceby the flow of the gas through a venturi throat 64a. As shown, the gassupply includes a gas supply tube 68, an adjustable valve and a nozzlefitting 72 which injects gas into the mixer 66. Each of the two valves70 is manually controlled by means of a rotatable knob 74 mountedoutside the post 12 on the outer end of a valve control shaft 76. Eachassembly of valve 70 and fitting 72 is supported in a fixed position byany suitable means and does not receive the weight of the burner 25 andassociated mixer tubes 54 inasmuch as the latter are supported by thefeet 60.

A modified I-I-shaped burner 25 is illustrated in FIG. 3, this burnerbeing substantially identical with the burner 25 except that theintegral internal partition 52' is located somewhat differently. in themodified burner 25 the burner of each arm 36 and 38 is coextensive withand parallel to the other arm and constitutes an entire leg of theH-shape. Therefore, in operation the burner 25 permits adjustment of thefront and rear portions of the cooking rack to different temperatures.

To place the gas grill of FIG. 1 in operation the user inserts a lightedmatch through the opening 23 and turns on the gas supply to the burnerarm 38 by means of the corresponding valve-control knob 74. The otherburner arm 36 is placed in operation, when desired, by turning on thegas supply to that arm, the flame from the arm 38 serving to light thegas automatically.

In one mode of operation only one burner arm, say the arm 38, islighted. Under these conditions that portion of the cooking rack 26which overlies the unlighted burner arm 36 receives heat energyprimarily in the form of radiant heat, and the other portion of thecooking rack 26 receives direct heat from the heated briquettes 28 andfrom the flame and hot gases. Flareups often encountered when grillinggreasy meats can be avoided by cooking such meats in the radiantlyheated zone, because the grease dripping from the meat will pass throughthe relatively unheated briquettes to the floor of the grill where itmay be drained off through a suitable aper ture. As is known, a flareupis the ignition and rapid burning of grease which sometimes results fromcontact of the grease with highly heated briquettes and/or with the opengas flame.

in a second mode of operation both burner arms 38 and 36 are lighted andadjusted to different heat outputs. By adjusting one burner arm to highheat and the other to low heat the user can, for example, cook one steakto a well done condition and another to a rare condition within aboutthe same period of time. If he is cooking chops or other pieces whichare apt to be of various sizes or thicknesses, he can cook the larger orthicker pieces over high heat and the smaller or thinner pieces over lowheat, and if necessary, he can shift the pieces from one end of the rackto the other, in order to achieve uniform cooking.

The elevations of the two parts of the cooking rack 26 can also beshifted as a further aid in cooking flexibility. The halves of the rackwill usually be positioned before the burner is lit, this beingaccomplished in the case of the lower position by tilting the rack piecefrom front to back in order to lower it past the upper lips 32a.

The operation of the grill when provided with the burner 25 of FIG. 3 isthe same as described above, except that adjustment of the two gasdelivery means controls the temperatures at the front and rear of thecooking rack 32.

What is claimed is:

l. in a gas-fired cooking grill: walls defining a cooking andsmoke-retaining enclosure; a horizontal cooking rack disposed in saidenclosure; a gas burner disposed below said coking rack, said burnerbeing a unitary hollow metal structure defining at least two hollow armswhich are provided with gas flame apertures and which extendhorizontally under different halves of said rack, said hollow metalstructure having at least one internal partition separating theinteriors of said arms from each other; and separate adjustablegas-delivery means cooperating with each of said arms whereby theoperator of the grill may adjust the temperature of said different partsof said cooking rack.

2. A gas-fired cooking grill as in claim 1 wherein said burner has twoarms, one of said arms extending under approximately one-half of saidcooking rack and the other of said arms extending under the other halfof said cooking rack.

3. A gas-fired cooking grill as in claim 2 wherein said gas burner isH-shaped and wherein said internal partition divides the interior ofsaid burner into two generally U-shaped arms.

4. A gas-fired cooking grill as in claim 2 wherein said gas burner isgenerally H-shaped and wherein said internal partition divides theinterior of said burner into two generally straight parallel arms.

5. A gas-fired cooking grill as in claim 2 wherein said hollow metalstructure is a one piece integrally cast structure.

6. A cooking grill as in claim 2 wherein said burner has two downwardlyfacing gas inlet apertures disposed on opposite sides of said internalpartition and wherein each gas-delivery means includes a verticallydisposed, venturi mixer tube having an upper end secured to said burnerand cooperating with one of said gas inlet apertures and a lower enddisposed adjacent a fixed gas discharge fitting so as to receive gastherefrom, said grill further including means supporting said burner andsaid mixer tubes on said enclosure whereby the weight of said burner andsaid mixer tubes does not rest on said gas discharge fitting.

7. A gas burner for use in an environment where it is desired to providetwo zones of different temperatures, said burner comprising anintegrally cast hollow metal structure having a plurality of horizontalarms extending outwardly from a common chamber, said arms being providedwith gas flame apertures over substantially their entire periphery, anda vertically disposed integrally cast internal partition within saidchamber separating the interior of the hollow structure into twogenerally equal portions, said chamber having a bottom wall providedwith two downwardly facing gas inlet apertures disposed on oppositesides of said partition, and an integrally cast foot depending from thebottom wall of each arm near the free end thereof for cooperating with afixed support structure.

8. A gas burner as in claim 7 in combination with a cooking grill havinga horizontal cooking rack, sidewalls surrounding said burner and saidrack, and a bottom wall on which said burner feet rest.

1. In a gas-fired cooking grill: walls defining a cooking andsmoke-retaining enclosure; a horizontal cooking rack disposed in saidenclosure; a gas burner disposed below said coking rack, said burnerbeing a unitary hollow metal structure defining at least two hollow armswhich are provided with gas flame apertures and which extendhorizontally under different halves of said rack, said hollow metalstructure having at least one internal partition separating theinteriors of said arms from each other; and separate adjustablegas-delivery means cooperating with each of said arms whereby theoperator of the grill may adjust the temperature of said different partsof said cooking rack.
 2. A gas-fired cooking grill as in claim 1 whereinsaid burner has two arms, one of said arms extending under approximatelyone-half of said cooking rack and the other of said arms extending underthe other half of said cooking rack.
 3. A gas-fired cooking grill as inclaim 2 wherein said gas burner is H-shaped and wherein said internalpartition divides the interior of said burner into two generallyU-shaped arms.
 4. A gas-fired cooking grill as in claim 2 wherein saidgas burner is generally H-shaped and wherein said internal partitiondivides the interior of said burner into two generally straight parallelarms.
 5. A gas-fired cooking grill as in claim 2 wherein said hollowmetal structure is a one-piece integrally cast structure.
 6. A cookinggrill as in claim 2 wherein said burner has two downwardly facing gasinlet apertures disposed on opposite sides of said internal partitionand wherein each gas-delivery means includes a vertically disposed,venturi mixer tube having an upper end secured to said burner andcooperating with one of said gas inlet apertures and a lower enddisposed adjacent a fixed gas discharge fitting so as to receive gastherefrom, said grill further including means supporting said burner andsaid mixer tubes on said enclosure whereby the weight of said burner andsaid mixer tubes does not rest on said gas discharge fitting.
 7. A gasburner for use in an environment where it is desired to provide twozones of different temperatures, said burner comprising an integrallycast hollow metal structure having a plurality of horizontal armsextending outwardly from a common chamber, said arms being provided withgas flame apertures over substantially their entire periphery, and avertically disposed integrally cast internal partition within saidchamber separating the interior of the hollow structure into twogenerally equal portions, said chamber having a bottom wall providedwith two downwardly facing gas inlet apertures disposed on oppositesides of said partition, and an integrally cast foot depending from thebottom wall of each arm near the free end thereof for cooperating with afixed support structure.
 8. A gas burner as in claim 7 in combinationwith a cooking grill having a horizontal cooking rack, sidewallssurrounding said burner and said rack, and a bottom wall on which saidburner feet rest.